From: "Tom Krajci" 
To: 
Reply-To: "Tom Krajci" 


>From: "Scott Berfield" 

>I am nearing the time to go to polishing on my 12+"and wanted to get a
>sense of how hard the pitch should be....

Texereau, appendix J, describes an easy, yet fairly precise test for pitch
hardness.  Make note of the temperature at which you performed the test. 
If nothing else, this test will give you a starting point, telling you what
air temp range would be good to use.  After that, your own experience and
results will help refine your technique.

In my case I found that if air temp was too cool, I would get rough
surfaces while polishing/figuring.  With the proper air temp my roughness
problems went away.  After some trial and error on your part you will find
what air temp range works best with your particular setup.

>Also, should I plan on using two different laps for polishing and
>figuring? If so, should the pitch be softer/harder for one than the
>other?

I always used the same lap for both.  Actually, I was able to make my lap
last so long that it would polish and figure several mirrors.

Tom Krajci
Tashkent, Uzbekistan

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